Due to its non-invasive and non-destructive nature, an ultrasound system has been extensively used for acquiring internal information of a target object in the medical profession, Since the ultrasound system may provide a high resolution image to a doctor without a surgical treatment, which is performed by directly incising and observing the target object, it is very helpful in the medical profession.
Generally, an ultrasound system includes a transmit/receive switch. The transmit/receive switch connects a transmitting unit with an ultrasound probe during a transmission period of an ultrasound signal to transmit a high voltage transmit signal from a receiving unit to an ultrasound probe. At the same time, the transmit/receive switch blocks a transmit signal to be propagated to the receiving unit. The transmit/receive switch connects the receiving unit with the ultrasound probe during a receiving period of an ultrasound signal to transmit the receive signal outputted from the ultrasound probe, which receives the ultrasound. signal reflected from a target object (i.e. ultrasound echo signal), to the receiving unit.
When an ultrasound image in thin depth is obtained with the conventional ultrasound system, a high voltage transmit signal is propagated to the receiving unit. This is because the transmit/receive switch cannot completely block the transmit signal to be propagated to the receiving unit. This not only affects the receiving unit but also reduces quality of the ultrasound image.